Q1: Which of the following approaches the ideal gas behaviour most closely ?

ANS:C - Superheated steam

The approach to ideal gas behavior depends on the conditions of the substance. Among the options provided:

• Wet steam: Wet steam is a mixture of saturated steam (vapor phase) and liquid water (liquid phase). It does not approach ideal gas behavior because it consists of both vapor and liquid phases, and its properties are influenced by the presence of liquid water droplets.
• Saturated steam: Saturated steam is steam that is in equilibrium with liquid water at a given temperature and pressure. While saturated steam exhibits some ideal gas behavior, it is not an ideal gas because its properties are still influenced by the phase change between vapor and liquid.
• Superheated steam: Superheated steam is steam that has been heated above its saturation temperature at a given pressure, resulting in a vapor phase with no liquid water present. Superheated steam can approach ideal gas behavior more closely than saturated steam because it behaves more like a gas with no phase change occurring.
• Saturated water: Saturated water refers to water that is in equilibrium with its vapor phase at a given temperature and pressure, similar to saturated steam but in the liquid phase. Saturated water does not exhibit ideal gas behavior because it is in the liquid phase, and its properties are different from those of an ideal gas.